This investigation was opened after ODI became aware of four engine compartment fires allegedly related to fuel leakage from the engine's fuel injector system.ODI conducted field examinations and communicated the identified concerns to Blue Bird.ODI also had discussions with Caterpillar, the engine manufacturer.On June 28th, 2010, Blue Bird filed two safety defect reports with NHTSA to address fuel lines that may crack at the fastening point to the common fuel rail. Safety recall campaign 10V-289 involves 3,686 school buses and safety recall campaign 10V-290 involves 103 non-school bus vehicles. The subject vehicles were equipped with the Caterpillar C-7-07 engine and it was determined that clamping of the #5 fuel line to the #6 fuel line and assembly stresses caused the #6 fuel line to fail. The remedy consist of replacing the #5 and #6 fuel lines and adding a new clamp to # 5 fuel line. Simultaneously with Blue Bird's decision to conduct the above recalls, Caterpillar Inc. filed a safety recall (10E-025) with NHTSA to perform the same remedy on 5,920 C7 series engines.Blue Bird engines are included in the Caterpillar recall.These recalls resolve the issues raised by this investigation. Therefore, this investigation is closed.